Keltec RDB Rifle 223Rem.With 11 game-changing innovations, the RDB™ is the new definition of bullpup. Its downward shell ejection system eliminates the side ejection disadvantage of ordinary bullpups. The result is casings that eject out of your line of sight and a truly ambidextrous, high performance rifle. The RDB is also adjustable for a wide variety of ammunition. It’s definitely the bullpup done right.